1
|
Zhang YW, Li JH, Teng S, Peng ZQ, Jamali MA. Quality improvement of prerigor salted ground chicken breast with basic amino acids at low NaCl level. Poult Sci 2023; 102:102871. [PMID: 37406440 PMCID: PMC10466239 DOI: 10.1016/j.psj.2023.102871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Revised: 06/09/2023] [Accepted: 06/09/2023] [Indexed: 07/07/2023] Open
Abstract
The prerigor salting effect is known to provide superior meat processing quality. Based on the urgent need for low salt meat products, the present study was undertaken to evaluate the prerigor salting effect when basic amino acids were introduced at 1% NaCl level. Ground chicken breast meat was salted with NaCl and basic amino acids at 30 min, 60 min, and 90 min postmortem for prerigor treatments. Compared to the 1% NaCl (w/w) treatment, the introduction of 0.06% basic amino acids (w/w) in the prerigor significantly led to an increase in myofibril fragmentation, myofibrillar protein solubility, emulsion activity, storage modulus change rate, gel water-holding capacity and hardness (P < 0.05). Furthermore, smaller and more uniformly sized droplets were produced in emulsion by basic amino acids. Individual basic amino acids had different prerigor salting effects, and it was indicated that basic amino acids could play a positive role in the prerigor salting effect when NaCl was reduced.
Collapse
Affiliation(s)
- Y W Zhang
- College of Food Science and Technology, National Center of Meat Quality and Safety Control, Nanjing Agricultural University, Nanjing 210095, China.
| | - J H Li
- College of Food Science and Technology, National Center of Meat Quality and Safety Control, Nanjing Agricultural University, Nanjing 210095, China
| | - S Teng
- College of Food Science and Technology, National Center of Meat Quality and Safety Control, Nanjing Agricultural University, Nanjing 210095, China
| | - Z Q Peng
- College of Food Science and Technology, National Center of Meat Quality and Safety Control, Nanjing Agricultural University, Nanjing 210095, China
| | - M A Jamali
- Department of Animal Products Technology, Sindh Agriculture University, Tandojam 70060, Pakistan
| |
Collapse
|
2
|
Glenn K, He J, Rochlin R, Teng S, Hecker JG, Novosselov I. Assessment of aerosol persistence in ICUs via low-cost sensor network and zonal models. Sci Rep 2023; 13:3992. [PMID: 36899063 PMCID: PMC10006437 DOI: 10.1038/s41598-023-30778-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Accepted: 03/01/2023] [Indexed: 03/12/2023] Open
Abstract
The COVID-19 pandemic raised public awareness about airborne particulate matter (PM) due to the spread of infectious diseases via the respiratory route. The persistence of potentially infectious aerosols in public spaces and the spread of nosocomial infections in medical settings deserve careful investigation; however, a systematic approach characterizing the fate of aerosols in clinical environments has not been reported. This paper presents a methodology for mapping aerosol propagation using a low-cost PM sensor network in ICU and adjacent environments and the subsequent development of the data-driven zonal model. Mimicking aerosol generation by a patient, we generated trace NaCl aerosols and monitored their propagation in the environment. In positive (closed door) and neutral-pressure (open door) ICUs, up to 6% or 19%, respectively, of all PM escaped through the door gaps; however, the outside sensors did not register an aerosol spike in negative-pressure ICUs. The K-means clustering analysis of temporospatial aerosol concentration data suggests that ICU can be represented by three distinct zones: (1) near the aerosol source, (2) room periphery, and (3) outside the room. The data suggests two-phase plume behavior: dispersion of the original aerosol spike throughout the room, followed by an evacuation phase where "well-mixed" aerosol concentration decayed uniformly. Decay rates were calculated for positive, neutral, and negative pressure operations, with negative-pressure rooms clearing out nearly twice as fast. These decay trends closely followed the air exchange rates. This research demonstrates the methodology for aerosol monitoring in medical settings. This study is limited by a relatively small data set and is specific to single-occupancy ICU rooms. Future work needs to evaluate medical settings with high risks of infectious disease transmission.
Collapse
Affiliation(s)
- K Glenn
- Department of Mechanical Engineering, University of Washington, Seattle, USA
| | - J He
- Department of Mechanical Engineering, University of Washington, Seattle, USA
| | - R Rochlin
- Department of Mechanical Engineering, University of Washington, Seattle, USA
| | - S Teng
- Department of Mechanical Engineering, University of Washington, Seattle, USA
| | - J G Hecker
- Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, USA
| | - I Novosselov
- Department of Mechanical Engineering, University of Washington, Seattle, USA.
| |
Collapse
|
3
|
He X, Yao Q, Fan D, Duan L, You Y, Lian W, Zhou Z, Teng S, Liang Z. Combination of cefotaxime and cisplatin specifically and selectively enhances anticancer efficacy in nasopharyngeal carcinoma. Curr Cancer Drug Targets 2023:CCDT-EPUB-129845. [PMID: 36847225 DOI: 10.2174/1568009623666230227162532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 12/30/2022] [Accepted: 01/11/2023] [Indexed: 03/01/2023]
Abstract
BACKGROUND HMOX1 has a dual role in cancers, especially involving chemoresistance. We demonstrate that cephalosporin antibiotics exert strong anticancer activity in nasopharyngeal carcinoma mainly via drastic upregulation of HMOX1. OBJECTIVES Cephalosporin antibiotics are commonly used for the treatment or prophylaxis of bacterial infectious diseases in cancer patients. It is unknown whether they lead to chemoresistance in cancer patients, especially in nasopharyngeal carcinoma patients, who are being treated or required prophylaxis for an infectious syndrome with cephalosporin antibiotics. METHODS MTT and clonogenic colony formation assays assessed the viability and proliferation of cultured cancer cells. Flow cytometry was used to detect apoptosis. Tumor growth was assessed using a xenograft model. Microarray and RT-qPCR expression analyses investigated differential gene expression. RESULTS Cefotaxime enhanced anticancer efficacy of cisplatin in nasopharyngeal carcinoma without enhancing the toxic side effects both in vitro and in vivo. However, cefotaxime significantly reduced the cytotoxicity of cisplatin in other cancer cell lines. Cefotaxime and cisplatin co-regulated 5 differential genes in CNE2 cells in a direction supporting the enhancement of anticancer efficacy, of which, THBS1 and LAPTM5 were further upregulated, STAG1, NCOA5, and PPP3CB were further downregulated. Out of the 18 apoptotic pathways significantly enriched in the combination group, THBS1 and HMOX1 overlapped in 14 and 12 pathways, respectively. Extrinsic apoptotic signaling pathway (GO: 2001236) was the only apoptotic pathway commonly enriched in cefotaxime group, cisplatin group and combination group, and THBS1 and HMOX1 were the overlapped genes of this pathway. THBS1 also overlapped in P53 signaling pathway and ECM-receptor interaction signaling pathway enriched by KEGG. CONCLUSION Cephalosporin antibiotics are chemosensitizers of conventional chemotherapeutic drugs in the chemotherapy of nasopharyngeal carcinoma, but they may lead to chemoresistance by cytoprotection in other cancers. Cefotaxime and cisplatin co-regulate THBS1, LAPTM5, STAG1, NCOA5 and PPP3CB suggesting their involvement in the enhancement of anticancer efficacy in nasopharyngeal carcinoma. Targeting of P53 signaling pathway and ECM-receptor interaction signaling pathway was correlated to the enhancement. With additional benefit for treatment or prophylaxis of an infectious syndrome, cephalosporin antibiotics can benefit the therapy of nasopharyngeal carcinoma either as anticancer agents or as chemosensitizers of chemotherapeutic drugs in combination chemotherapy.
Collapse
Affiliation(s)
- Xiaoqiong He
- School of Public Health, Kunming Medical University, Kunming, Yunnan Province 650500, China
| | - Qian Yao
- Institute of Yunnan Tumor, the Third Affiliated Hospital of Kunming Medical University, Kunming, Yunnan Province 650118, China
| | - Dan Fan
- School of Public Health, Kunming Medical University, Kunming, Yunnan Province 650500, China
| | - Ling Duan
- School of Public Health, Kunming Medical University, Kunming, Yunnan Province 650500, China
| | - Yutong You
- School of Public Health, Kunming Medical University, Kunming, Yunnan Province 650500, China
| | - Wenjing Lian
- School of Public Health, Kunming Medical University, Kunming, Yunnan Province 650500, China
| | - Zhangping Zhou
- School of Public Health, Kunming Medical University, Kunming, Yunnan Province 650500, China
| | - Song Teng
- School of Public Health, Kunming Medical University, Kunming, Yunnan Province 650500, China
| | - Zhuoxuan Liang
- School of Public Health, Kunming Medical University, Kunming, Yunnan Province 650500, China
| |
Collapse
|
4
|
Hecker JG, He J, Rochlin R, Brannen C, Teng S, Glenn K, Novosselov I. Measuring aerosols in the operating theatre and beyond using a real-time sensor network. Anaesthesia 2022; 77:1097-1105. [PMID: 36047649 DOI: 10.1111/anae.15842] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/02/2022] [Indexed: 11/27/2022]
Abstract
The ability to measure and track aerosols in the vicinity of patients with suspected or confirmed COVID-19 is highly desirable. At present, there is no way to measure and track, in real time, the sizes, dispersion and dilution/disappearance of aerosols that are generated by airway manipulations such as mask ventilation; tracheal intubation; bronchoscopy; dental and gastro-intestinal endoscopy procedures; or by vigorous breathing, coughing or exercise. We deployed low-cost photoelectric sensors in five operating theatres between surgical cases. We measured and analysed dilution and exfiltration of aerosols we generated to evaluate air handling and dispersion under real-world conditions. These data were used to develop a model of aerosol persistence. We found significant variation between different operating theatres. Equipment placement near air vents affects air flows, impacting aerosol movement and elimination patterns. Despite these impediments, air exchange in operating theatres is robust and prolonged fallow time before theatre turnover may not be necessary. Significant concentrations of aerosols are not seen in adjoining areas outside of the operating theatre. These models and dispersion rates can predict aerosol persistence in operating theatres and other clinical areas and potentially facilitate quantification of risk, with obvious and far-reaching implications for designing, evaluating and confirming air handling in non-medical environments.
Collapse
Affiliation(s)
- J G Hecker
- Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA, USA
| | - J He
- Department of Mechanical Engineering, University of Washington, Seattle, WA, USA
| | - R Rochlin
- Department of Mechanical Engineering, University of Washington, Seattle, WA, USA
| | - C Brannen
- Peri-operative Services, Department of Nursing, University of Washington, Seattle, WA, USA
| | - S Teng
- Department of Mechanical Engineering, University of Washington, Seattle, WA, USA
| | - K Glenn
- Department of Mechanical Engineering, University of Washington, Seattle, WA, USA
| | - I Novosselov
- Department of Mechanical Engineering, University of Washington, Seattle, WA, USA
| |
Collapse
|
5
|
He X, Yao Q, Fan D, Duan L, You Y, Liang W, Zhou Z, Teng S, Liang Z, Hall DD, Song LS, Chen B. Cephalosporin antibiotics specifically and selectively target nasopharyngeal carcinoma through HMOX1-induced ferroptosis. Life Sci 2021; 277:119457. [PMID: 33831425 DOI: 10.1016/j.lfs.2021.119457] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Revised: 03/21/2021] [Accepted: 03/27/2021] [Indexed: 12/14/2022]
Abstract
AIMS Many antibiotics derived from mold metabolites have been found to possess anticarcinogenic properties. We aimed to investigate whether they may elicit anticancer activity, especially against nasopharyngeal carcinoma. MAIN METHODS The response of nasopharyngeal and other carcinoma cell lines to cephalosporin antibiotics was evaluated in vitro and in vivo. MTT and clonogenic colony formation assays assessed the viability and proliferation of cultured cells. Flow cytometry was used to assess cell cycle parameters and apoptotic markers. Tumor growth was determined using a xenograft model in vivo. Microarray and RT-qPCR expression analyses investigate differential gene expression. Mechanistic assessment of HMOX1 in cefotaxime-mediated ferroptosis was tested with Protoporphyrin IX zinc. KEY FINDINGS Cephalosporin antibiotics showed highly specific and selective anticancer activity on nasopharyngeal carcinoma CNE2 cells both in vitro and vivo with minimal toxicity. Cefotaxime sodium significantly regulated 11 anticancer relevant genes in CNE2 cells in a concentration-dependent manner. Pathway analyses indicate apoptotic and the ErbB-MAPK-p53 signaling pathways are significantly enriched. HMOX1 represents the top one ranked upregulated gene by COS and overlaps with 16 of 42 enriched apoptotic signaling pathways. Inhibition of HMOX1 significantly reduced the anticancer efficacy of cefotaxime in CNE2 cells. SIGNIFICANCE Our discovery is the first to highlight the off-label potential of cephalosporin antibiotics as a specific and selective anticancer drug for nasopharyngeal carcinoma. We mechanistically show that induction of ferroptosis through HMOX1 induction mediates cefotaxime anticancer activity. Our findings provide an alternative treatment for nasopharyngeal carcinoma by showing that existing cephalosporin antibiotics are specific and selective anticancer drugs.
Collapse
Affiliation(s)
- Xiaoqiong He
- School of Public Health, Kunming Medical University, Kunming, Yunnan, China.
| | - Qian Yao
- Institute of Yunnan Cancer, the Third Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
| | - Dan Fan
- School of Public Health, Kunming Medical University, Kunming, Yunnan, China
| | - Ling Duan
- School of Public Health, Kunming Medical University, Kunming, Yunnan, China
| | - Yutong You
- School of Public Health, Kunming Medical University, Kunming, Yunnan, China
| | - Wenjing Liang
- School of Public Health, Kunming Medical University, Kunming, Yunnan, China
| | - Zhangping Zhou
- School of Public Health, Kunming Medical University, Kunming, Yunnan, China
| | - Song Teng
- School of Public Health, Kunming Medical University, Kunming, Yunnan, China
| | - Zhuoxuan Liang
- School of Public Health, Kunming Medical University, Kunming, Yunnan, China
| | - Duane D Hall
- Department of Medicine, Carver College of Medicine, The University of Iowa, Iowa City, IA, USA
| | - Long-Sheng Song
- Department of Medicine, Carver College of Medicine, The University of Iowa, Iowa City, IA, USA
| | - Biyi Chen
- Department of Medicine, Carver College of Medicine, The University of Iowa, Iowa City, IA, USA.
| |
Collapse
|
6
|
Xu J, Zhou H, Teng S, Hu Z. Radical apical lymph node dissection guided by carbon nanoparticles in laparoscopic rectal cancer surgery - a video vignette. Colorectal Dis 2019; 21:1453. [PMID: 31400184 DOI: 10.1111/codi.14821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 07/24/2019] [Indexed: 02/08/2023]
Affiliation(s)
- J Xu
- Department of Surgery, Shanghai Baoshan District Combining Traditional Chinese and Western Medicine Hospital, Shanghai, China
| | - H Zhou
- Division of Colorectal Surgery, Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - S Teng
- Division of Colorectal Surgery, Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Z Hu
- Division of Colorectal Surgery, Changzheng Hospital, Second Military Medical University, Shanghai, China
| |
Collapse
|
7
|
Teng S, Ren Z, Zhao K. Vagal Stimulation Facilitates Improving Effects of Ranolazine on Cardiac Function in Rats with Chronic Ischemic Heart Failure. Curr Mol Med 2018; 18:36-43. [PMID: 29879885 DOI: 10.2174/1566524018666180608085330] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Revised: 05/18/2018] [Accepted: 06/04/2018] [Indexed: 11/22/2022]
Affiliation(s)
- S. Teng
- Department of Emergency Medicine, The Fourth Clinical Hospital of Harbin Medical University, Harbin 150001, China
| | - Z. Ren
- Department of Emergency Medicine, The Fourth Clinical Hospital of Harbin Medical University, Harbin 150001, China
| | - K. Zhao
- Department of Emergency Medicine, The Fourth Clinical Hospital of Harbin Medical University, Harbin 150001, China
| |
Collapse
|
8
|
Tang X, Teng S, Petri M, Krettek C, Liu C, Jagodzinski M. The effect of anti-inflammatory and antifibrotic agents on fibroblasts obtained from arthrofibrotic tissue: An in vitro and in vivo study. Bone Joint Res 2018; 7:213-222. [PMID: 29922438 PMCID: PMC5987688 DOI: 10.1302/2046-3758.73.bjr-2017-0219.r2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Objectives The aims of this study were to determine whether the administration of anti-inflammatory and antifibrotic agents affect the proliferation, viability, and expression of markers involved in the fibrotic development of the fibroblasts obtained from arthrofibrotic tissue in vitro, and to evaluate the effect of the agents on arthrofibrosis prevention in vivo. Methods Dexamethasone, diclofenac, and decorin, in different concentrations, were employed to treat fibroblasts from arthrofibrotic tissue (AFib). Cell proliferation was measured by DNA quantitation, and viability was analyzed by Live/Dead staining. The levels of procollagen type I N-terminal propeptide (PINP) and procollagen type III N-terminal propeptide (PIIINP) were evaluated with enzyme-linked immunosorbent assay (ELISA) kits. In addition, the expressions of fibrotic markers were detected by real-time polymerase chain reaction (PCR). Fibroblasts isolated from healthy tissue (Fib) served as control. Further, a rabbit model of joint contracture was used to evaluate the antifibrotic effect of the three different agents. Results Dexamethasone maintained the viability and promoted the proliferation of AFib. Diclofenac decreased the viability and inhibited the cell proliferation during the first week of cultivation. However, decorin inhibited AFib proliferation and downregulated the expressions of fibrotic markers. Additionally, decorin could improve the flexion contracture angle and inhibit the deposition of interstitial matrix components in the rabbit joint model. Conclusion Decorin decreased the expression of myofibroblast markers in AFib, inhibited the proliferation of AFib, and prevented the initial procedure of arthrofibrosis in vivo, suggesting that decorin could be a promising treatment to inhibit the development of arthrofibrosis.Cite this article: X. Tang, S. Teng, M. Petri, C. Krettek, C. Liu, M. Jagodzinski. The effect of anti-inflammatory and antifibrotic agents on fibroblasts obtained from arthrofibrotic tissue: An in vitro and in vivo study. Bone Joint Res 2018;7:213-222. DOI: 10.1302/2046-3758.73.BJR-2017-0219.R2.
Collapse
Affiliation(s)
- X Tang
- Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - S Teng
- Department of Orthopedic Trauma, Hannover Medical School (MH), Hannover, Germany
| | - M Petri
- Department of Orthopedic Trauma, Hannover Medical School (MH), Hannover, Germany
| | - C Krettek
- Department of Orthopedic Trauma, Hannover Medical School (MH), Hannover, Germany
| | - C Liu
- Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - M Jagodzinski
- Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| |
Collapse
|
9
|
Teng S, Thomson PA, McCarthy S, Kramer M, Muller S, Lihm J, Morris S, Soares DC, Hennah W, Harris S, Camargo LM, Malkov V, McIntosh AM, Millar JK, Blackwood DH, Evans KL, Deary IJ, Porteous DJ, McCombie WR. Rare disruptive variants in the DISC1 Interactome and Regulome: association with cognitive ability and schizophrenia. Mol Psychiatry 2018; 23:1270-1277. [PMID: 28630456 PMCID: PMC5984079 DOI: 10.1038/mp.2017.115] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 03/20/2017] [Accepted: 03/27/2017] [Indexed: 12/20/2022]
Abstract
Schizophrenia (SCZ), bipolar disorder (BD) and recurrent major depressive disorder (rMDD) are common psychiatric illnesses. All have been associated with lower cognitive ability, and show evidence of genetic overlap and substantial evidence of pleiotropy with cognitive function and neuroticism. Disrupted in schizophrenia 1 (DISC1) protein directly interacts with a large set of proteins (DISC1 Interactome) that are involved in brain development and signaling. Modulation of DISC1 expression alters the expression of a circumscribed set of genes (DISC1 Regulome) that are also implicated in brain biology and disorder. Here we report targeted sequencing of 59 DISC1 Interactome genes and 154 Regulome genes in 654 psychiatric patients and 889 cognitively-phenotyped control subjects, on whom we previously reported evidence for trait association from complete sequencing of the DISC1 locus. Burden analyses of rare and singleton variants predicted to be damaging were performed for psychiatric disorders, cognitive variables and personality traits. The DISC1 Interactome and Regulome showed differential association across the phenotypes tested. After family-wise error correction across all traits (FWERacross), an increased burden of singleton disruptive variants in the Regulome was associated with SCZ (FWERacross P=0.0339). The burden of singleton disruptive variants in the DISC1 Interactome was associated with low cognitive ability at age 11 (FWERacross P=0.0043). These results identify altered regulation of schizophrenia candidate genes by DISC1 and its core Interactome as an alternate pathway for schizophrenia risk, consistent with the emerging effects of rare copy number variants associated with intellectual disability.
Collapse
Affiliation(s)
- S Teng
- Stanley Institute for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
- Department of Biology, Howard University, Washington DC, USA
| | - P A Thomson
- Centre for Genomic and Experimental Medicine, MRC/University of Edinburgh Institute of Genetics & Molecular Medicine, Western General Hospital, Edinburgh, UK
- Centre for Cognitive Ageing and Cognitive Epidemiology, Edinburgh, UK
| | - S McCarthy
- Stanley Institute for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - M Kramer
- Stanley Institute for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - S Muller
- Stanley Institute for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - J Lihm
- Stanley Institute for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - S Morris
- Centre for Genomic and Experimental Medicine, MRC/University of Edinburgh Institute of Genetics & Molecular Medicine, Western General Hospital, Edinburgh, UK
| | - D C Soares
- Centre for Genomic and Experimental Medicine, MRC/University of Edinburgh Institute of Genetics & Molecular Medicine, Western General Hospital, Edinburgh, UK
| | - W Hennah
- Institute for Molecular Medicine, Finland FIMM, University of Helsinki, Helsinki, Finland
| | - S Harris
- Centre for Genomic and Experimental Medicine, MRC/University of Edinburgh Institute of Genetics & Molecular Medicine, Western General Hospital, Edinburgh, UK
- Centre for Cognitive Ageing and Cognitive Epidemiology, Edinburgh, UK
| | - L M Camargo
- UCB New Medicines, One Broadway, Cambridge, MA, USA
| | - V Malkov
- Genetics and Pharmacogenomics, MRL, Merck & Co, Boston, MA, USA
| | - A M McIntosh
- Division of Psychiatry, University of Edinburgh, Royal Edinburgh Hospital, Edinburgh, UK
| | - J K Millar
- Centre for Genomic and Experimental Medicine, MRC/University of Edinburgh Institute of Genetics & Molecular Medicine, Western General Hospital, Edinburgh, UK
| | - D H Blackwood
- Division of Psychiatry, University of Edinburgh, Royal Edinburgh Hospital, Edinburgh, UK
| | - K L Evans
- Centre for Cognitive Ageing and Cognitive Epidemiology, Edinburgh, UK
| | - I J Deary
- Centre for Cognitive Ageing and Cognitive Epidemiology, Edinburgh, UK
- Department of Psychology, University of Edinburgh, Edinburgh, UK
| | - D J Porteous
- Centre for Genomic and Experimental Medicine, MRC/University of Edinburgh Institute of Genetics & Molecular Medicine, Western General Hospital, Edinburgh, UK
- Centre for Cognitive Ageing and Cognitive Epidemiology, Edinburgh, UK
| | - W R McCombie
- Stanley Institute for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| |
Collapse
|
10
|
Zhao SY, Wang J, Teng S, Zhou J, Lin XY, Song W, Wu YD, Wei Y. [Observation on intestinal viral shedding time of hand, foot and mouth disease induced by coxsackievirus A6]. Zhonghua Er Ke Za Zhi 2017; 55:369-372. [PMID: 28482389 DOI: 10.3760/cma.j.issn.0578-1310.2017.05.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To observe the intestinal viral shedding time in patients with hand, food and mouth disease (HFMD) induced by coxsackievirus A6 (CA6). Method: Throat swab specimens and stool specimens of HFMD children were collected from those admitted to Hangzhou Children's Hospital between May and October 2015, while fluorescence quantitative PCR was used to detect the viral load.Eeighteen cases of HFMD children were followed up, who were confirmed as CA6 infection via laboratory tests.Stool specimen was collected every 4-7 days, and fluorescence PCR was used for virus nucleic acid detection until the stool viral nucleic acids of infected children turned to be negative.The intestinal virus shedding time of CA6-infected HFMD was compared with the intestinal virus shedding time of 65 children with enterovirus 71 (EV71) infection and 44 children with coxsackievirus A16 (CA16) infection of the previous studies (from May to September 2012). Result: The median stool viral load was 25×10(5) copies/ml (55×10(4) copies/mL, 9×10(6) copies/ml) in CA6-infected children.The numbers of stool virus nucleic acid turning negative were 0 case, 4 cases, 9 cases, 3 cases and 2 cases in 18 children at 1st, 2nd, 3rd, 4th, 5th weeks. At 5th week, the stool virus nucleic acid of children in CA6 group all turned to be negative.The positive rates of stool virus nucleic acid in EV71 group and CA16 group at the 5th week, however, were 31% and 27% respectively.There were statistically significant differences in distribution of positive rate of stool virus nucleic acid between CA6 infected children with EV71 and CA16 infected children (χ(2)=13.894, 10.698, P<0.05). Conclusion: The longest intestinal virus shedding time for CA6-infected HFMD children was 5 weeks, which is obviously shorter than that of EV71- infected children and CA16-infected children.
Collapse
Affiliation(s)
- S Y Zhao
- Department of Infectious Diseases, Hangzhou Children's Hospital, Hangzhou 310014, China
| | | | | | | | | | | | | | | |
Collapse
|
11
|
Teng S, Guo Z, Peng H, Xing G, Chen H, He B, McClure M, Mu Q. High-frequency repetitive transcranial magnetic stimulation over the left DLPFC for major depression: Session-dependent efficacy: A meta-analysis. Eur Psychiatry 2017; 41:75-84. [DOI: 10.1016/j.eurpsy.2016.11.002] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 11/02/2016] [Accepted: 11/02/2016] [Indexed: 01/18/2023] Open
Abstract
AbstractBackgroundDepression is a major debilitating psychiatric disorder. Current antidepressant drugs are often associated with side effects or treatment resistance. The aim of this meta-analysis was to evaluate therapeutic effects of high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) in major depression (MD).MethodsThe medical data bases of PubMed, Medline, Embase and Cochrane Central Register were searched for randomized controlled trials (RCTs) reporting the therapeutic effects of high-frequency rTMS for depression, which were published in English between January 1990 and June 2016. The index terms were “depress*”, “depression” and “transcranial magnetic stimulation”. Depression outcome data of different sessions (5, 10, 15, and 20 sessions of rTMS treatment) were extracted and synthesized by calculating standardized mean difference (SMD) with 95% confidence intervals (CI) by using a random-effect model. Within each session group, the subgroup analyses based on the number of pulses (≤ 1000, 1200–1500, 1600–1800, and 2000–3000) were also conducted.ResultsThirty RCTs with a total of 1754 subjects including 1136 in the rTMS group and 618 in the sham group were included in this meta-analysis. rTMS had a significant overall therapeutic effect on depression severity scores (SMD = −0.73, P < 0.00001). The five, 10, 15, 20 sessions of rTMS treatments yielded the significant mean effect sizes of −0.43, −0.60, −1.13, and −2.74, respectively. In the four groups (5, 10, 15, 20 sessions), the maximal mean effect size was all obtained in the subgroup of 1200–1500 pulses per day (−0.97, −1.14, −1.91, −5.47; P < 0.05).ConclusionsThe increasing of HF-rTMS sessions is associated with the increased efficacy of HF-rTMS in reducing depressed patients’ symptom severity. A total number of pulses of 1200–1500 per day appear to deliver the best antidepressant effects of HF-rTMS.
Collapse
|
12
|
Teng S, Tebby C, Barcellini-Couget S, De Sousa G, Brochot C, Rahmani R, Pery ARR. Analysis of real-time mixture cytotoxicity data following repeated exposure using BK/TD models. Toxicol Appl Pharmacol 2016; 305:118-126. [PMID: 27317371 DOI: 10.1016/j.taap.2016.06.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 06/06/2016] [Accepted: 06/13/2016] [Indexed: 11/23/2022]
Abstract
Cosmetic products generally consist of multiple ingredients. Thus, cosmetic risk assessment has to deal with mixture toxicity on a long-term scale which means it has to be assessed in the context of repeated exposure. Given that animal testing has been banned for cosmetics risk assessment, in vitro assays allowing long-term repeated exposure and adapted for in vitro - in vivo extrapolation need to be developed. However, most in vitro tests only assess short-term effects and consider static endpoints which hinder extrapolation to realistic human exposure scenarios where concentration in target organs is varies over time. Thanks to impedance metrics, real-time cell viability monitoring for repeated exposure has become possible. We recently constructed biokinetic/toxicodynamic models (BK/TD) to analyze such data (Teng et al., 2015) for three hepatotoxic cosmetic ingredients: coumarin, isoeugenol and benzophenone-2. In the present study, we aim to apply these models to analyze the dynamics of mixture impedance data using the concepts of concentration addition and independent action. Metabolic interactions between the mixture components were investigated, characterized and implemented in the models, as they impacted the actual cellular exposure. Indeed, cellular metabolism following mixture exposure induced a quick disappearance of the compounds from the exposure system. We showed that isoeugenol substantially decreased the metabolism of benzophenone-2, reducing the disappearance of this compound and enhancing its in vitro toxicity. Apart from this metabolic interaction, no mixtures showed any interaction, and all binary mixtures were successfully modeled by at least one model based on exposure to the individual compounds.
Collapse
Affiliation(s)
- S Teng
- Models for Toxicology and Ecotoxicology Unit, INERIS, Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte, France
| | - C Tebby
- Models for Toxicology and Ecotoxicology Unit, INERIS, Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte, France
| | - S Barcellini-Couget
- ODESIA Neosciences, Sophia Antipolis, 400 route des chappes, 06903 Sophia Antipolis, France
| | - G De Sousa
- INRA, ToxAlim, 400 route des Chappes, BP, 167 06903 Sophia Antipolis, Cedex, France
| | - C Brochot
- Models for Toxicology and Ecotoxicology Unit, INERIS, Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte, France
| | - R Rahmani
- INRA, ToxAlim, 400 route des Chappes, BP, 167 06903 Sophia Antipolis, Cedex, France
| | - A R R Pery
- AgroParisTech, UMR 1402 INRA-AgroParisTech Ecosys, 78850 Thiverval Grignon, France; INRA, UMR 1402 INRA-AgroParisTech Ecosys, 78850 Thiverval Grignon, France.
| |
Collapse
|
13
|
Teng S, Barcellini-Couget S, Beaudouin R, Brochot C, Desousa G, Rahmani R, Pery A. BK/TD models for analyzing in vitro impedance data on cytotoxicity. Toxicol Lett 2015; 235:96-106. [DOI: 10.1016/j.toxlet.2015.03.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 03/24/2015] [Accepted: 03/27/2015] [Indexed: 02/01/2023]
|
14
|
Lin D, Jiang Q, Zheng K, Chen S, Zhou H, Gong X, Xu J, Teng S, Dong Y. Mutation of the rice ASL2 gene encoding plastid ribosomal protein L21 causes chloroplast developmental defects and seedling death. Plant Biol (Stuttg) 2015; 17:599-607. [PMID: 25280352 DOI: 10.1111/plb.12271] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Accepted: 09/22/2014] [Indexed: 05/19/2023]
Abstract
The plastid ribosome proteins (PRPs) play important roles in plastid protein biosynthesis, chloroplast differentiation and early chloroplast development. However, the specialised functions of individual protein components of the chloroplast ribosome in rice (Oryza sativa) remain unresolved. In this paper, we identified a novel rice PRP mutant named asl2 (Albino seedling lethality 2) exhibiting an albino, seedling death phenotype. In asl2 mutants, the alteration of leaf colour was associated with chlorophyll (Chl) content and abnormal chloroplast development. Through map-based cloning and complementation, the mutated ASL2 gene was isolated and found to encode the chloroplast 50S ribosome protein L21 (RPL21c), a component of the chloroplast ribosome large subunit, which was localised in chloroplasts. ASL2 was expressed at a higher level in the plumule and leaves, implying its tissue-specific expression. Additionally, the expression of ASL2 was regulated by light. The transcript levels of the majority of genes for Chl biosynthesis, photosynthesis and chloroplast development were strongly affected in asl2 mutants. Collectively, the absence of functional ASL2 caused chloroplast developmental defects and seedling death. This report establishes the important role of RPL21c in chloroplast development in rice.
Collapse
Affiliation(s)
- D Lin
- Development Center of Plant Germplasm Resources, College of Life and Environment Sciences, Shanghai Normal University, Shanghai, China
| | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Teng S, Whitney D. The auditory flash-drag effect: Distortion of auditory space by visual motion. J Vis 2011. [DOI: 10.1167/11.11.794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
|
16
|
Finck RH, Davis RJ, Teng S, Goldfinger D, Ziman AF, Lu Q, Yuan S. Performance of an automated solid-phase red cell adherence system compared with that of a manual gel microcolumn assay for the identification of antibodies eluted from red blood cells. Immunohematology 2011; 27:1-5. [PMID: 22356479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
IgG antibodies coating red blood cells (RBCs) can be removed by elution procedures and their specificity determined by antibody identification studies. Although such testing is traditionally performed using the tube agglutination assay, prior studies have shown that the gel microcolumn (GMC) assay may also be used with comparable results. The purpose of this study was to compare an automated solid-phase red cell adherence (SPRCA) system with a GMC assay for the detection of antibodies eluted from RBCs. Acid eluates from 51 peripheral blood (PB) and 7 cord blood (CB) samples were evaluated by both an automated SPRCA instrument and a manual GMC assay. The concordance rate between the two systems for peripheral RBC samples was 88.2 percent (45 of 51), including cases with alloantibodies (n = 8), warm autoantibodies (n = 12), antibodies with no identifiable specificity (n = 2), and negative results (n = 23). There were six discordant cases, of which four had alloantibodies (including anti-Jka, -E, and -e) demonstrable by the SPRCA system only. In the remaining 2 cases, anti-Fya and antibodies with no identifiable specificity were demonstrable by the GMC assay only. All seven CB specimens produced concordant results, showing anti-A (n = 3), -B (n = 1), maternal anti-Jka (n = 2), or a negative result (n = 1). Automated SPRCA technology has a performance that is comparable with that of a manual GMC assay for identifying antibodies eluted from PB and CB RBCs.
Collapse
Affiliation(s)
- R H Finck
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, 10833 Le Conte Avenue, CHS A7-149, Box 107, Los Angeles, CA 90095, USA
| | | | | | | | | | | | | |
Collapse
|
17
|
Kumar P, Fischbach NA, Brahmer JR, Spigel DR, Beatty S, Teng S, Flick ED, Sing A, Lynch TJ. Baseline (BL) radiographic characteristics and severe pulmonary hemorrhage (SPH) in bevacizumab (BV)-treated non-small cell lung cancer (NSCLC) patients (pt): Results from ARIES, an observational cohort study (OCS). J Clin Oncol 2010. [DOI: 10.1200/jco.2010.28.15_suppl.7619] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
18
|
Wozniak AJ, Garst J, Jahanzeb M, Kosty MP, Vidaver R, Beatty S, Teng S, Flick ED, Sing A, Lynch TJ. Clinical outcomes (CO) for special populations of patients (pts) with advanced non-small cell lung cancer (NSCLC): Results from ARIES, a bevacizumab (BV) observational cohort study (OCS). J Clin Oncol 2010. [DOI: 10.1200/jco.2010.28.15_suppl.7618] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
19
|
Teng S, Whitney D. Auditory stimuli elicit spatially specific responses in visual cortex. J Vis 2010. [DOI: 10.1167/7.9.328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
|
20
|
Teng S, Whitney D. Position discrimination of auditory stimuli in early visual cortex. J Vis 2010. [DOI: 10.1167/8.6.166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
|
21
|
Lynch TJ, Brahmer J, Fischbach N, Garst J, Kumar P, Spigel DR, Teng S, Vidaver R, Wang L, Navarro W. Preliminary treatment patterns and safety outcomes for non-small cell lung cancer (NSCLC) from ARIES, a bevacizumab treatment observational cohort study (OCS). J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.8077] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
22
|
Teng S, Michonova-Alexova E, Alexov E. Approaches and resources for prediction of the effects of non-synonymous single nucleotide polymorphism on protein function and interactions. Curr Pharm Biotechnol 2008; 9:123-33. [PMID: 18393868 DOI: 10.2174/138920108783955164] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Almost all (99.9%) nucleotide bases are exactly the same in all people, however, the remaining 0.1% account for about 1.4 million locations where single-base DNA differences/polymorphisms (SNPs) occur in humans. Some of these SNPs, called non-synonymous SNPs (nsSNPs), result in a change of the amino acid sequences of the corresponding proteins affecting protein functions and interactions. This review summarizes the plausible mechanisms that nsSNPs may affect the normal cellular function. It outlines the approaches that have been developed in the past to predict the effects caused by nsSNPs with special emphasis on the methods that use structural information. The review provides systematic information on the available resources for predicting the effects of nsSNPs and includes a comprehensive list of existing SNP databases and their features. While nsSNPs resulting in amino acid substitution in the core of a protein may affect protein stability irreversibly, the effect of an nsSNP resulting to a mutation at the surface of a protein or at the interface of protein-protein complexes, could, in principle be, subject of drug therapy. The importance of understanding the effects caused by nsSNP mutations at the protein-protein and protein-DNA interfaces is outlined.
Collapse
Affiliation(s)
- S Teng
- Department of Physics, Clemson University, Clemson, SC 29634, USA
| | | | | |
Collapse
|
23
|
Abstract
BACKGROUND AND PURPOSE Activation of the pregnane X receptor (PXR) has been shown to protect against cholestatic hepatotoxicity. As PXR alters the expression of numerous hepatic bile acid transporters, we sought to delineate their potential role in hepatoprotection. EXPERIMENTAL APPROACH Wild-type (PXR+/+) and PXR-null (PXR-/-) mice were fed a 1% cholic acid (CA) diet with or without the PXR activator, PCN. Liver function was assessed along with the corresponding changes in hepatic gene expression. KEY RESULTS CA administration caused significant hepatotoxicity in PXR+/+ mice and was associated with induction of several FXR and PXR regulated genes, which encode for bile acid transport and metabolizing proteins. Compared to CA alone, co-administration of PCN to CA-fed PXR+/+ mice significantly decreased hepatotoxicity and was associated with induction of MRP3 mRNA as well as CYP3A11 mRNA and functional activity. Unexpectedly, PXR-/- mice, which expressed significantly higher basal and CA-induced levels of MRP2, MRP3, OSTalpha, OSTbeta, OATP2 and CYP3A11, were dramatically less sensitive to CA hepatotoxicity than PXR+/+ mice. CONCLUSIONS Protection of PXR+/+ mice against CA-induced hepatotoxicity by PCN is associated with the induction of MRP3 and CYP3A11 expression. Resistance against CA-induced hepatotoxicity in PXR-/- mice may result from higher basal and induced expression of bile acid transporters, particularly MRP3. These findings emphasize the importance of transport by MRP3 and metabolism as major protective pathways against cholestatic liver injury.
Collapse
Affiliation(s)
- S Teng
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto Toronto, Ontario, Canada
| | - M Piquette-Miller
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto Toronto, Ontario, Canada
- Author for correspondence:
| |
Collapse
|
24
|
|
25
|
|
26
|
Teng S, Sun J, Irby R, Hamilton AD, Sebti S, Yeatman TJ. v-Src transformation is mediated through farnesylated proteins. J Surg Res 2001; 99:343-6. [PMID: 11469908 DOI: 10.1006/jsre.2001.6184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Src is an oncoprotein which has been implicated in a number of human malignancies in which it has been shown to be overexpressed and highly activated. The precise mechanism of Src transformation, however, is still poorly understood. We hypothesized that Ras and other farnesylated proteins may mediate Src transformation. To test this hypothesis, v-Src-transfected rat fibroblasts (3Y1) were treated every 72 h with a 15 microM concentration of a farnesyl-transferase inhibitor (FTI). At 2 weeks, a focus formation assay was performed to assess transformation potential. Untreated and FTI-treated v-Src-transfected 3Y1 cells formed a mean of 39 (+/-2.6) and 29.8 (+/-2.9) foci per well, respectively. This 24% decrease was judged to be statistically significant (P = 0.02). Moreover, foci (>90%) in the FTI-treated wells were also consistently smaller than foci in the untreated wells. Western blots with antibody directed toward H-Ras confirmed complete inhibition of Ras farnesylation in the treated cell lines. The specificity of this inhibition was verified by Western blot using antibody specific for Rap1A. The transforming potential of v-Src is inhibited, but not eliminated by FTI treatment. This suggests that v-Src transformation is mediated in part by farnesylated proteins, one of which may be Ras.
Collapse
Affiliation(s)
- S Teng
- Department of Surgery, Ochsner Clinic and Hospital, New Orleans, Louisiana, USA
| | | | | | | | | | | |
Collapse
|
27
|
Galati G, Teng S, Moridani MY, Chan TS, O'Brien PJ. Cancer chemoprevention and apoptosis mechanisms induced by dietary polyphenolics. Drug Metabol Drug Interact 2001; 17:311-49. [PMID: 11201302 DOI: 10.1515/dmdi.2000.17.1-4.311] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
This review summarises current knowledge on the various molecular chemopreventive or therapeutic mechanisms that may be involved when the administration of flavonoids or polyphenols prevented chemical carcinogenesis in animal models. These mechanisms can be subdivided into the following: 1) the molecular mechanisms involved in preventing carcinogen metabolic activation, 2) the molecular mechanisms for preventing tumour cell proliferation by inactivation or downregulation of prooxidant enzymes or signal transduction enzymes, 3) the molecular cell death mechanisms for the induction of tumour cell death (apoptosis) and the molecular mechanisms for the inhibition of isolated mitochondria functions. Many of the flavonoids and polyphenols found in diets, supplements or herbal medicine were also ranked using "accelerated cytotoxic mechanism screening" by a combinatorial approach utilising isolated rat hepatocytes. A strong correlation of an early collapse of the mitochondrial membrane potential and cell death was found for most of the cytotoxic polyphenols but did not occur with non-toxic polyphenols. This screening could prove useful for eliminating polyphenols that have the potential for adverse health effects and for selecting safe and effective polyphenolic candidates for further development as supplements for preventing cancer or cardiovascular disease. Safety concerns of flavonoid/polyphenol supplements are also reviewed.
Collapse
Affiliation(s)
- G Galati
- Department of Pharmacology, University of Toronto, Ontario, Canada
| | | | | | | | | |
Collapse
|
28
|
Moridani MY, Khan S, Chan T, Teng S, Beard K, O'Brien PJ. Cytochrome P450 2E1 metabolically activates propargyl alcohol: propiolaldehyde-induced hepatocyte cytotoxicity. Chem Biol Interact 2001; 130-132:931-42. [PMID: 11306107 DOI: 10.1016/s0009-2797(00)00246-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Pargyline, an antihypertensive agent and monoamine oxidase inhibitor, induces hepatic GSH depletion and hepatotoxicity in vivo in rats [E.G. De Master, H.W. Sumner, E. Kaplan, F. N. Shirota, H.T. Nagasawa, Toxicol. Appl. Pharmacol. 65 (1982) 390-401]. Propargyl alcohol (2-propyn-1-ol), because of its structural similarity to allyl alcohol, was thought to be activated by alcohol dehydrogenase. However, it is a poor substrate compared to allyl alcohol and it was therefore proposed that propargyl alcohol-induced liver injury involved metabolic activation by catalase/H(2)O(2) [E.G. De Master, T. Dahlseid, B. Redfern, Chem. Res. Toxicol. 7 (1994) 414-419]. In the following we showed that; (1) propargyl alcohol-induced cytotoxicity was markedly enhanced in CYP 2E1-induced hepatocytes and prevented by various CYP 2E1 inhibitors but was only slightly affected when alcohol dehydrogenase was inhibited with methylpyrazole/DMSO or when catalase was inactivated with azide or aminotriazole, (2) hepatocyte GSH depletion preceded cytotoxicity and was inhibited by cytochrome P450 inhibitors but not by catalase/alcohol dehydrogenase inhibitors. GSH conjugate formation during propargyl alcohol metabolism by microsomal mixed function oxidase in the presence of GSH was also prevented by anti-rat CYP 2E1 or CYP 2E1 inhibitors, (3) cytotoxicity was prevented when lipid peroxidation was inhibited with antioxidants, desferoxamine (ferric chelator) or dithiothreitol. Propargyl alcohol-induced cytotoxicity and reactive oxygen species formation were markedly increased in GSH-depleted hepatocytes. All of this evidence suggests that propargyl alcohol-induced cytotoxicity involves metabolic activation by CYP 2E1 to form propiolaldehyde that causes hepatocyte lysis as a result of GSH depletion and lipid peroxidation.
Collapse
Affiliation(s)
- M Y Moridani
- Faculty of Pharmacy, University of Toronto, 19 Russell Street, M5S 2S2, Toronto, Ont., Canada
| | | | | | | | | | | |
Collapse
|
29
|
Teng S, Beard K, Pourahmad J, Moridani M, Easson E, Poon R, O'Brien PJ. The formaldehyde metabolic detoxification enzyme systems and molecular cytotoxic mechanism in isolated rat hepatocytes. Chem Biol Interact 2001; 130-132:285-96. [PMID: 11306052 DOI: 10.1016/s0009-2797(00)00272-6] [Citation(s) in RCA: 152] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The toxicity and carcinogenicity of formaldehyde (HCHO) has been attributed to its ability to form adducts with DNA and proteins. A marked decrease in mitochondrial membrane potential and inhibition of mitochondrial respiration that was accompanied by reactive oxygen species formation occurred when isolated rat hepatocytes were incubated with low concentrations of HCHO in a dose-dependent manner. Hepatocyte GSH was also depleted by HCHO in a dose-dependent manner. At higher HCHO concentrations, lipid peroxidation ensued followed by cell death. Cytotoxicity studies were conducted in which isolated hepatocytes exposed to HCHO were treated with inhibitors of HCHO metabolising enzymes. There was a marked increase in HCHO cytotoxicity when either alcohol dehydrogenase or aldehyde dehydrogenase was inhibited. Inhibition of GSH-dependent HCHO dehydrogenase activity by prior depletion of GSH markedly increased hepatocyte susceptibility to HCHO. In each case, cytotoxicity was dose-dependent and corresponded with a decrease in hepatocyte HCHO metabolism and increased lipid peroxidation. Antioxidants and iron chelators protected against HCHO cytotoxicity. Cytotoxicity was also prevented, when cyclosporine or carnitine was added to prevent the opening of the mitochondrial permeability transition pore which further suggests that HCHO targets the mitochondria. Thus, HCHO-metabolising gene polymorphisms would be expected to have toxicological consequences on an individual's susceptibility to HCHO toxicity and carcinogenesis.
Collapse
Affiliation(s)
- S Teng
- Faculty of Pharmacy, University of Toronto, 19 Russell St., Ont., M5S 2S2, Toronto, Canada
| | | | | | | | | | | | | |
Collapse
|
30
|
Qian Q, He P, Teng S, Zeng DL, Zhu LH. [QTLs analysis of tiller angle in rice (Oryza sativa L.)]. Yi Chuan Xue Bao 2001; 28:29-32. [PMID: 11209708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
Tiller angle is one of important characters that constitute plant type with great significance in breading. A pair of japonica/indica lines, which were significantly different in tiller angle, were used in this study. A DH population were constructed via anther culture of F1 hybrids. The tiller angles of 115 DH lines were measured. QTL analysis was conducted based on the constructed molecular linkage map. Three QTLs (qTA-9a, qTA-9b and qTA-12) were detected on chromosome 9 and 12 respectively, Their variation were 22.7%, 11.9% and 20.9% respectively and their additive effects were all negative, showing this character was controlled by genes from big tiller angle parent ZYQ8. The application of the tiller angle that was controlled by major genes and minor genes in rice breeding is also discussed.
Collapse
Affiliation(s)
- Q Qian
- China National Rice Research Institute, Hangzhou 310006, China
| | | | | | | | | |
Collapse
|
31
|
Abstract
The skull is distinguished from other parts of the skeleton by its composite construction. The sutures between bony elements provide for interstitial growth of the cranium, but at the same time they alter the transmission of stress and strain through the skull. Strain gages were bonded to the frontal and parietal bones of miniature pigs and across the interfrontal, interparietal and coronal sutures. Strains were recorded 1) during natural mastication in conjunction with electromyographic activity from the jaw muscles and 2) during stimulation of various cranial muscles in anesthetized animals. Vault sutures exhibited vastly higher strains than did the adjoining bones. Further, bone strain primarily reflected torsion of the braincase set up by asymmetrical muscle contraction; the tensile axis alternated between +45 degrees and -45 degrees depending on which diagonal masseter/temporalis pair was most active. However, suture strains were not related to overall torsion but instead were responses to local muscle actions. Only the coronal suture showed significant strain (tension) during jaw opening; this was caused by the contraction of neck muscles. All sutures showed strain during jaw closing, but polarity depended on the pattern of muscle usage. For example, masseter contraction tensed the coronal suture and the anterior part of the interfrontal suture, whereas the temporalis caused compression in these locations. Peak tensile strains were larger than peak compressive strains. Histology suggested that the skull is bent at the sutures, with the ectocranial surface tensed and the endocranial surface predominantly compressed. Collectively, these results indicate that skulls with patent sutures should be analyzed as complexes of independent parts rather than solid structures.
Collapse
Affiliation(s)
- S W Herring
- Department of Orthodontics, University of Washington, Seattle, Washington 98195, USA.
| | | |
Collapse
|
32
|
Teng S, Dupont E, McCann C, Wang J, Bolano M, Durand K, Peltz E, Bass SS, Cantor A, Ku NN, Cox CE. Do cytokeratin-positive-only sentinel lymph nodes warrant complete axillary lymph node dissection in patients with invasive breast cancer? Am Surg 2000; 66:574-8. [PMID: 10888134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
The small number of nodes harvested with lymphatic mapping and sentinel lymph node (SLN) biopsy has allowed a more detailed pathologic examination of those nodes. Immunohistochemical stains for cytokeratin (CK-IHC) have been used in an attempt to minimize the false negative rate for SLN mapping. This study examines the value of CK-IHC positivity in predicting further lymph node involvement in the axillary basin. From April 1998 through May 1999, 519 lymphatic mappings and SLN biopsies were performed for invasive breast cancer. SLNs were examined by imprint cytology, hematoxylin and eosin (H&E), and CK-IHC. Patients with evidence of metastatic disease by any of the above techniques were eligible for complete axillary node dissection (CAND). The frequency with which these modalities predicted further lymph node involvement in the axillary basin was compared. Of the 519 lymphatic mappings, 39 patients (7.5%) had a CK-IHC-positive-only SLN. Five (12.8%) of these 39 patients had at least 2 SLNs positive by CK-IHC. Twenty-six of the CK-IHC-positive-only patients underwent CAND. Three of these 26 patients (11.5%) had additional metastases identified after CAND. The sensitivity levels with which each modality detected further axillary lymph node involvement were as follows: CK-IHC, 98 per cent; H&E, 94 per cent; and imprint cytology, 87 per cent. A logistic regression to compare the prognostic value of the three modalities was performed. All were significant, with odds ratios of 19.1 for CK-IHC (P = 0.015), 5.3 for H&E (P = 0.033), and 3.86 for imprint cytology (P = 0.0059). These data validate the enhanced detection of CK-IHC for the evaluation of SLNs. Detection of CK-IHC-positive SLNs appears to warrant CAND in patients with invasive breast cancer. However, the therapeutic value of CAND or adjuvant therapies based on CK-IHC-positive SLNs would be best answered by prospective randomized trials.
Collapse
Affiliation(s)
- S Teng
- H. Lee Moffitt Cancer Center at the University of South Florida, Tampa, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Sgroi DC, Teng S, Robinson G, LeVangie R, Hudson JR, Elkahloun AG. In vivo gene expression profile analysis of human breast cancer progression. Cancer Res 1999; 59:5656-61. [PMID: 10582678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
The development and use of molecular-based therapy for breast cancer and other human malignancies will require a detailed molecular genetic analysis of patient tissues. The recent development of laser capture microdissection and high density cDNA arrays now provides a unique opportunity to generate gene expression profiles of cells from various stages of tumor progression as it occurs in the actual neoplastic tissue milieu. We report the combined use of laser capture microdissection and high-throughput cDNA microarrays to monitor in vivo gene expression levels in purified normal, invasive, and metastatic breast cell populations from a single patient. These in vivo gene expression profiles were verified by real-time quantitative PCR and immunohistochemistry. The combined use of laser capture microdissection and cDNA microarray analysis provides a powerful new approach to elucidate the in vivo molecular events surrounding the development and progression of breast cancer and is generally applicable to the study of malignancy.
Collapse
Affiliation(s)
- D C Sgroi
- Department of Pathology, Harvard Medical School, Massachusetts General Hospital, Boston 02129, USA
| | | | | | | | | | | |
Collapse
|
34
|
Zhang R, Teng S, Ma Y. [Reconstruction and repair after resection of soft tissue sarcoma]. Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi 1999; 13:18-20. [PMID: 12080751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
OBJECTIVE To emphasize the importance of reconstruction and repair after resection of soft tissue sarcoma. METHODS From November 1990 to November 1996, in 107 cases of soft tissue sarcoma 32 cases had received various reconstructive or reparative operations. Among the 32 cases, 4 cases were primary sarcomas and 28 cases were recurrent sarcomas. In surgical grading, 3 cases were of I B, 3 cases of II A and 26 cases of II B. Radical resection was performed in 13 cases, widen local resection in 17 cases and local excision in 2 cases. After operation, 13 cases received chemotherapy and 7 cases received radiotherapy. Reconstruction of blood vessels was performed in 3 cases, reconstruction of kinetic function in 16 cases, and repair of defect was carried out in 23 cases. RESULTS Thirty patients were followed up for 4 months to 6 years and 6 months. The clinical results showed that the local control rate of sarcoma was 80%, limb-salvage rate after reconstruction of blood vessels was 100%, the excellent and good rate after reconstruction of kinetic function was 87.5%, and the survival rate of the tissue flap of transplantation and transposition was 96%. CONCLUSION It was concluded that the reconstruction and repair after resection of soft tissue sarcoma was the extension of operative treatment, and was very important in lowering the recurrence rate and improving the life quality of the sufferings.
Collapse
Affiliation(s)
- R Zhang
- Department of Bone and Soft Tissue Tumor, Tianjin Cancer Hospital, Tianjin, P. R. China 300060
| | | | | |
Collapse
|
35
|
Abstract
BACKGROUND: Esophageal cancer is a highly lethal malignancy. Esophageal resection remains the primary treatment in most centers. A number of approaches to esophageal resection have been described. METHODS: The authors review the current approaches to esophageal resection and adjuvant therapy for esophageal cancer. RESULTS: Transthoracic, transhiatal, and minimally invasive techniques are currently employed in esophageal surgery for malignancy. A number of authors favor extended mediastinal and cervical lymphadenectomy in hopes of improving survival. Combined chemotherapy and radiotherapy in the neoadjuvant setting appears to offer some promise. CONCLUSIONS: No consensus of opinion exists regarding the optimal approach or extent of esophageal resection for cancer. Prospective, randomized trials of neoadjuvant therapy may determine its efficacy. Newer approaches may enhance quality of life.
Collapse
Affiliation(s)
- S Teng
- Gastrointestinal Tumor Program, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida 33612, USA
| | | |
Collapse
|
36
|
Abstract
Several authors have speculated that muscles contracting adjacent to bony surfaces may cause compressive loads against the bone and thus influence skull development. This study was undertaken to evaluate the premise of this argument. A flat, semiconductor pressure transducer was surgically placed on bony surfaces beneath muscle attachments. Pressures were recorded during normal mastication (n = 7) and while overlying muscles were stimulated in anesthetized pigs (n = 15). The transducer was highly specific; no pressure was recorded in quiescent or passively stretched muscles or when other muscles were stimulated. Contraction of the overlying muscles exerted high normal loads on the bone, always exceeding systolic blood pressure (16 kPa). Temporal fossa pressure during mastication followed temporalis electromyographic (EMG) signals with a lag period approximating the twitch contraction time. When three different sites were compared in anesthetized animals, compressive load was highest on the temporal fossa (111.4 +/- 56.5 kPa, n = 15), intermediate on the mandibular angle (58.4 +/- 28.3 kPa, n = 4), and lowest on the medial side of the zygomatic arch (37.2 +/- 19.7 kPa, n = 15). Pressure amplitudes were not related to body size or relative muscle size. Muscle complexity and compartmental constraints did appear to influence pressure. Disruption of the external aponeurosis of the masseter decreased pressure on the mandibular angle by 45%, confirming the importance of tendinous constraint in determining pressure production. Thus, contracting muscles exert substantial but site-specific compressive loads on adjacent bone surfaces.
Collapse
Affiliation(s)
- S Teng
- Department of Orthodontics, University of Washington, Seattle 98195, USA
| | | |
Collapse
|
37
|
Affiliation(s)
- O Prakash
- Laboratory of Molecular Oncology, Alton Ochsner Medical Foundation, New Orleans, Louisiana 70002, USA
| | | | | | | | | | | | | | | |
Collapse
|
38
|
Prakash O, Teng S, Ali M, Zhu X, Coleman R, Dabdoub RA, Chambers R, Aw TY, Flores SC, Joshi BH. The human immunodeficiency virus type 1 Tat protein potentiates zidovudine-induced cellular toxicity in transgenic mice. Arch Biochem Biophys 1997; 343:173-80. [PMID: 9224727 DOI: 10.1006/abbi.1997.0168] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
3'-Azido-2',3'-dideoxythymidine (AZT, zidovudine) is the principal antiretroviral agent in the treatment of AIDS. Although beneficial, AZT remains restricted for human usage because of its severe toxic effects. We examined the AZT sensitivity in transgenic mice expressing HIV-1 one-exon-encoded 72 amino acid Tat (Tat72) and full-length 86 amino acid Tat (Tat86) proteins. Administration of AZT (1 mg/ml) in drinking water for 1 week resulted in a three- to fourfold decrease in hematopoietic progenitors from bone marrow in Tat mice compared to AZT-treated nontransgenic controls as determined by erythroid and granulocyte/macrophage colony-forming unit assays. In liver and thymus, two of the tissues examined, AZT treatment of Tat mice resulted in as much as 80-90% suppression of Mn-superoxide dismutase (Mn-SOD) activity. Other parameters associated with loss of Mn-SOD such as increase in carbonyl proteins and decrease of sulfhydryl content were also significantly enhanced by AZT in Tat mice. Our in vivo study suggests that AZT therapy is associated with oxidative damage affecting cellular functions in several tissues and that Tat is one of the contributory factors in AZT-induced toxicities. The findings of AZT-induced oxidative damage may help to improve the therapeutic index of AZT and other related drugs in AIDS patients.
Collapse
Affiliation(s)
- O Prakash
- Laboratory of Molecular Oncology, Alton Ochsner Medical Foundation, New Orleans, Louisiana 70121, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
39
|
Marks L, Teng S, Artun J, Herring S. Reaction strains on the condylar neck during mastication and maximum muscle stimulation in different condylar positions: an experimental study in the miniature pig. J Dent Res 1997; 76:1412-20. [PMID: 9207775 DOI: 10.1177/00220345970760071201] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Most researchers agree that the primate temporomandibular joint (TMJ) is loaded compressively during function and that condylar position must play a role in mediating such loads. However, the precise nature of that role remains unclear. Using a pig model in this study, we attempted to analyze strain on the neck of the condyle during normal mastication and during simulated function in different condylar positions. Miniature three-element rosette strain gauges were bonded to the lateral surface of the condylar neck in 4 female miniature pigs (one per condyle). Measurements of strain were made during normal mastication and with the pigs under general anesthesia during maximum stimulation of the masseter and temporalis muscles in each of five condylar positions--centric occlusion, centric relation, anterior, relaxed and wide open--established through use of acrylic splints. Condylar position was evaluated by superimposition of lateral and dorsoventral cephalograms, with measurement of horizontal and vertical changes in location of implants placed on the zygomatic arch. As in primates, the TMJ was found to be load-bearing during mastication, with compressive strain oriented approximately perpendicular to the occlusal plane. In 3 pigs, strain was higher during balancing than during working function. During stimulation, the TMJ reaction strains were significantly lower with the condyles in the anterior position compared with the other positions, and the compressive strain was directed more anteriorly along the neck of the condyle in that position.
Collapse
Affiliation(s)
- L Marks
- University of Washington Department of Orthodontics, Seattle, USA
| | | | | | | |
Collapse
|
40
|
Abstract
BACKGROUND Stereological analysis of trabecular bone structure may reveal information about regional variations in stress distribution, especially in areas like the zygomatic arch in which those variations are difficult to assess mechanically. This study investigates regional differences in trabecular orientation, thickness, and density in the zygomatic and squamosal bones of pigs. METHODS Zygomatic arches were serially sectioned frontally (n = 4), horizontally (n = 4), or parasagittally (n = 4), at a thickness of 0.8 mm. Sections were viewed under a stereomicroscope; video-images were digitized and analyzed with an automated program. RESULTS All regions were anisotropic. Predominant orientation of trabeculae differed between and within bones. Three main patterns were seen. Anteriorly, zygomatic trabeculae were mainly arranged vertically and anteroposteriorly (relative to the occlusal plane). Posteriorly, including the jaw joint region, the squamosal featured primarily mediolateral trabeculae. In the midsection of the arch, where the two bones overlap, the trabeculae displayed a predominantly anteroposterior orientation with a secondary mediolateral peak. Trabeculae were typically 0.3-0.4 mm wide and occupied 40-50% of the area of the sections with few regional variations. CONCLUSIONS Trabecular bone in the pig zygomatic arch is arranged orthogonally, relative to the occlusal plane. In conjunction with information from strain gauge recording, these data suggest that the zygomatic bone is bent in the parasagittal plane whereas the squamosal is bent out-of-plane. The mediolateral trabeculae in the posterior regions are consistent with a cantilever effect at the jaw joint.
Collapse
Affiliation(s)
- S Teng
- Department of Orthodontics, University of Washington, Seattle 98195-746, USA.
| | | | | | | |
Collapse
|
41
|
Abstract
PURPOSE In orthognathic surgery, rigid fixation is routinely used to hold together bone fragments that may experience heavy force from attached masticatory muscles. Internal fixation plates are assumed to hold bony parts rigidly, but the mobility at such sites subjected to normal masticatory function has not been measured. The purpose of this study was to investigate in vivo the degree to which a linear plate immobilizes separated bones, specifically sutures. MATERIALS AND METHODS Three female miniature pigs (Sus scrofa) had 1.3-mm Synthes titanium plates placed across the suture in the zygomatic arch. Foil strain gauges were used to record load deformation in the zygomatic and squamosal (temporal) bones and across the vertical and horizontal parts of the suture. Strain was recorded in vivo during mastication and in anesthetized pigs with electrical stimulation of masticatory muscles. RESULTS Strain at the suture was not reduced from normal levels. The plate induced increases in strain within the bones, but the changes were slight. CONCLUSION The results indicate that linear "rigid fixation" does not immobilize sutures.
Collapse
Affiliation(s)
- J A Freeman
- Department of Orthodontics, University of Washington, Seattle 98195-7446, USA
| | | | | |
Collapse
|
42
|
Abstract
BACKGROUND The transmission of force through the skull is complicated by the irregular form of the bones, the interposed sutures, and the multiplicity of loads from the teeth, muscles, and environment. The in vivo relationship between bone strain and muscle function in the mammalian skull is best investigated empirically. METHODS We studied the zygomatic arch of pigs (Sus scrofa) by simultaneous strain gauge recording and electromyography. Seventeen juvenile animals were used, employing multiple strain gauges arranged either in rosettes or strips. Strain was recorded during mastication and muscle stimulations. Bony architecture was examined on sectioned specimens. RESULTS Strain patterns were complex even in this beamlike structure. During masseteric contraction, the more anterior zygomatic bone showed in-plane bending such that its lower border became more convex, and the major principal strain axis (tension) was parallel to the masseter muscle. The posterior squamosal bone was slightly bent in the opposite direction, and the major principal strain was rotated 45-60 degrees from the masseteric line of action. Strain magnitudes in the squamosal were larger than those in the zygomatic. Woven bone composing the surface of the arch appeared denser in the zygomatic bone, where its predominant orientation corresponded with compressive strain. In the squamosal bone trabeculae were more regularly arranged, but their orientation did not correspond with strain axes. CONCLUSIONS The magnitude differences are probably related to the different architecture of the zygomatic and squamosal bones, whereas the different strain patterns primarily reflect the influence of the sutures in selectively damping or transmitting loads. In particular, the zygomatic bone may be loaded by three-point, distributed-load bending, whereas the squamosal, loaded at only two points, may be sheared. We conclude that each cranial bone functions in a unique strain environment, with the sutures serving to redirect loading.
Collapse
Affiliation(s)
- S W Herring
- Department of Orthodontics, University of Washington, Seattle 98195-7446, USA
| | | | | | | | | |
Collapse
|
43
|
Abstract
Stereologic studies of trabecular architecture suggest that the pig mandibular condyle is strongest when loaded supero-inferiorly, and that stress is concentrated in the antero-inferior region (Teng and Herring, 1995). To test these hypotheses, we investigated the uni-axial mechanical properties of 22 pig mandibular condyles in three loading directions at a mean strain rate of 0.14 (+/- 0.12)% s-1. A total of 91 rectangular beam specimens (averaging 9.0 mm x 6.0 mm x 5.0 mm) was tested. For each specimen, 5 or 6 non-destructive tests were performed before compressive failure. Strain in both longitudinal and transverse directions was measured by foil strain gauges on the central part of the specimen. Data were normalized at a strain rate of 0.1% s-1, specimen length of 9 mm, and cross-sectional area of 30.25 mm2. Generally, modulus of elasticity (E) and ultimate stress (sigma u) in the anterior regions of the condyle were greater than those in the posterior. E, sigma u, and Poisson's ratio (upsilon) were significantly different among the test directions, but ultimate strain (epsilon u) was not. The highest values of E (4.04 GPa), sigma u (14.97 MPa), and rho (0.81 g/cm3) were seen in the anterior inferior/middle region under supero-inferior loading. The lowest values (0.94 GPa for E, 2.38 MPa for sigma u, and 0.52 g/cm3 for rho) were found in the inferior/posterior region in medio-lateral loading. Although the mechanical properties of the condyle vary depending upon location, these results verify that the condyle is strongest and stiffest under compressive loads in the supero-inferior direction, and that the anterior-inferior region is particularly strong and stiff.
Collapse
Affiliation(s)
- S Teng
- University of Washington, Department of Orthodontics, Seattle 98195-7446, USA
| | | |
Collapse
|
44
|
Abstract
The morphology of bony trabeculae can indicate the loading conditions that predominate near joint surfaces. This study reports principal orientation, anisotropy, thickness, separation and density of trabeculae in the mandibular condyle of pigs. Condyles from slaughterhouse pigs were serially sectioned anteroposteriorly (n = 4), mediolaterally (n = 5) or horizontally (n = 4) at 0.8 mm using a diamond saw. Sections were viewed under a stereomicroscope and video-images of four sites per section were digitized. Anteroinferior sites had thicker, more widely spaced trabeculae than other sites, suggesting a concentration of stress. Anisotropy in the frontal plane was greater than in the sagittal or the horizontal planes, indicating a more consistent direction of loading in the frontal plane. Principal orientation in the frontal sections was perpendicular to the occlusal plane and did not differ among the sites. In the sagittal sections, trabeculae in inferior sites were variably oriented, whereas those in superior sites sloped posterosuperiorly, possibly reflecting shearing loads resulting from translational movements. In the horizontal sections, the trabeculae were oriented perpendicular to the frontal plane, suggesting an anteroposterior component of loading. Compared to cancellous bone from other locations, the trabeculae of the mandibular condyle are robust and dense, strongly supporting the notion that the temporomandibular joint is heavily loaded.
Collapse
Affiliation(s)
- S Teng
- University of Washington, Department of Orthodontics, Seattle 98195, USA
| | | |
Collapse
|
45
|
Vanselow J, Grabczyk E, Ping J, Baetscher M, Teng S, Fishman MC. GAP-43 transgenic mice: dispersed genomic sequences confer a GAP-43-like expression pattern during development and regeneration. J Neurosci 1994; 14:499-510. [PMID: 8301350 PMCID: PMC6576807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Using transgenic mice, we have examined the expression pattern conferred by regions of genomic GAP-43 coupled to beta-galactosidase. We demonstrate that gene constructions that include the GAP-43 5'-flanking region along with sufficient sequences of the first intron drive beta-galactosidase (lacZ) expression to mimic in many regards the complex spatial and temporal pattern of endogenous GAP-43 expression. Transgene expression reaches peak levels during development, and persists at high levels in particular adult brain regions, such as the hippocampus and olfactory bulb. The inclusion of a stretch of the first intron in the construction is necessary to prevent expression outside of the nervous system, indicating that some of the cell specificity of GAP-43 expression is due to suppression of expression in inappropriate tissues. Injury caused by sciatic nerve crush causes reexpression of the transgene in adult sensory and motor neurons. This genomic region of GAP-43, therefore, includes elements responsive to neuronal growth signals that regulate both development and regeneration.
Collapse
Affiliation(s)
- J Vanselow
- Developmental Biology Laboratory, Massachusetts General Hospital, Boston
| | | | | | | | | | | |
Collapse
|
46
|
Teng S. [Post-extrasystole potentiation in patients with organic heart diseases]. Zhonghua Xin Xue Guan Bing Za Zhi 1985; 13:261-3. [PMID: 2426074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|